1. Field of the Invention
The present invention relates to a system for a rapid testing to determine the structural integrity of cylinder blocks of internal combustion engines. This testing uses hydraulic pressure, rather than mechanical loading, to simulate the force of combustion gases on the cylinder block, and if desired, the cylinder head.
2. Disclosure Information
Bench testing of internal combustion engine componentry has general taken the form of mechanical testing, as shown in U.S. Pat. No. 3,690,162 (Stecher), in which pistons and piston rings are subjected to intense vibratory forces by mechanical excitation systems. It has also been known to subject cylinder blocks to mechanical forces imposed by press-like mechanisms which load the engine block in a manner which is thought to simulate, albeit very inaccurately, forces imposed on the block when the engine is firing. U.S. Pat. No. 5,054,314 (Cofflard et al.) discloses a system for using an injection pump to test an engine cylinder head by subjecting the cylinder head to hydraulic pressure. Unfortunately, the system of the '314 patent contains nothing regarding the engine cylinder block, nor does it appear to allow rapid testing of multiple cylinders in an engine so as to more accurately simulate the effect of firing stresses upon the engine. Although it is known to test more than one cylinder of an engine with a hydraulic pressure test, it is not known to use a system in which multiple cylinders are operated with a fewer number of servo valves than the maximum number of cylinders being tested, with multiple cylinders being supplied with hydraulic oil by a single servo valve, according to the present invention.
A system according to the present invention allows rapid life cycle testing of engine cylinder blocks in a manner which closely simulates the stresses imposed by combustion gases upon the cylinder block, and if desired, the cylinder head. According to one aspect of the present invention, the cylinder block is stressed sequentially according to the engine's firing order, with the result that the stresses imposed on the block by the hydraulic fluid may more closely simulate the stresses arising in a firing engine.
Other advantages of the present invention will become apparent to the reader of this specification.